/****************************************************************************
 * drivers/misc/optee_msg.h
 *
 * SPDX-License-Identifier: BSD-2-Clause
 * Copyright (c) 2015-2020, Linaro Limited
 *
 ****************************************************************************/

#ifndef __DRIVERS_MISC_OPTEE_MSG_H
#define __DRIVERS_MISC_OPTEE_MSG_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <sys/types.h>
#include <nuttx/bits.h>

/* This file defines the OP-TEE message protocol (ABI) used to communicate
 * with an instance of OP-TEE running in secure world.
 *
 * This file is divided into two sections.
 * 1. Formatting of messages.
 * 2. Requests from normal world
 */

/****************************************************************************
 * Part 1 - formatting of messages
 ****************************************************************************/

#define OPTEE_MSG_ATTR_TYPE_NONE                0x0
#define OPTEE_MSG_ATTR_TYPE_VALUE_INPUT         0x1
#define OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT        0x2
#define OPTEE_MSG_ATTR_TYPE_VALUE_INOUT         0x3
#define OPTEE_MSG_ATTR_TYPE_RMEM_INPUT          0x5
#define OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT         0x6
#define OPTEE_MSG_ATTR_TYPE_RMEM_INOUT          0x7
#define OPTEE_MSG_ATTR_TYPE_FMEM_INPUT          OPTEE_MSG_ATTR_TYPE_RMEM_INPUT
#define OPTEE_MSG_ATTR_TYPE_FMEM_OUTPUT         OPTEE_MSG_ATTR_TYPE_RMEM_OUTPUT
#define OPTEE_MSG_ATTR_TYPE_FMEM_INOUT          OPTEE_MSG_ATTR_TYPE_RMEM_INOUT
#define OPTEE_MSG_ATTR_TYPE_TMEM_INPUT          0x9
#define OPTEE_MSG_ATTR_TYPE_TMEM_OUTPUT         0xa
#define OPTEE_MSG_ATTR_TYPE_TMEM_INOUT          0xb

#define OPTEE_MSG_ATTR_TYPE_MASK                GENMASK(7, 0)

/* Meta parameter to be absorbed by the Secure OS and not passed
 * to the Trusted Application.
 * Currently only used with OPTEE_MSG_CMD_OPEN_SESSION.
 */

#define OPTEE_MSG_ATTR_META                     BIT(8)

/* Pointer to a list of pages used to register user-defined SHM buffer.
 * Used with OPTEE_MSG_ATTR_TYPE_TMEM_*.
 * buf_ptr should point to the beginning of the buffer. Buffer will contain
 * list of page addresses. OP-TEE core can reconstruct contiguous buffer from
 * that page addresses list. Page addresses are stored as 64 bit values.
 * Last entry on a page should point to the next page of buffer.
 * Every entry in buffer should point to a 4k page beginning (12 least
 * significant bits must be equal to zero).
 *
 * 12 least significant bits of optee_msg_param.u.tmem.buf_ptr should hold
 * page offset of user buffer.
 *
 * So, entries should be placed like members of this structure:
 *
 * struct page_data {
 *   uint64_t pages_array[
 * OPTEE_MSG_NONCONTIG_PAGE_SIZE/sizeof(uint64_t) - 1];
 *   uint64_t next_page_data;
 * };
 *
 * Structure is designed to exactly fit into the page size
 * OPTEE_MSG_NONCONTIG_PAGE_SIZE which is a standard 4KB page.
 *
 * The size of 4KB is chosen because this is the smallest page size for ARM
 * architectures. If REE uses larger pages, it should divide them to 4KB
 * ones.
 */

#define OPTEE_MSG_ATTR_NONCONTIG                BIT(9)

/* Memory attributes for caching passed with temp memrefs. The actual value
 * used is defined outside the message protocol with the exception of
 * OPTEE_MSG_ATTR_CACHE_PREDEFINED which means the attributes already
 * defined for the memory range should be used. If optee_smc.h is used as
 * bearer of this protocol OPTEE_SMC_SHM_* is used for values.
 */

#define OPTEE_MSG_ATTR_CACHE_SHIFT              16
#define OPTEE_MSG_ATTR_CACHE_MASK               GENMASK(2, 0)
#define OPTEE_MSG_ATTR_CACHE_PREDEFINED         0

/* Same values as TEE_LOGIN_* from TEE Internal API */

#define OPTEE_MSG_LOGIN_PUBLIC                  0x00000000
#define OPTEE_MSG_LOGIN_USER                    0x00000001
#define OPTEE_MSG_LOGIN_GROUP                   0x00000002
#define OPTEE_MSG_LOGIN_APPLICATION             0x00000004
#define OPTEE_MSG_LOGIN_APPLICATION_USER        0x00000005
#define OPTEE_MSG_LOGIN_APPLICATION_GROUP       0x00000006

/* Page size used in non-contiguous buffer entries */

#define OPTEE_MSG_NONCONTIG_PAGE_SIZE           4096

#define OPTEE_MSG_FMEM_INVALID_GLOBAL_ID        0xffffffffffffffff

/* struct optee_msg_param_tmem - temporary memory reference parameter
 * buf_ptr:    Address of the buffer
 * size:       Size of the buffer
 * shm_ref:    Temporary shared memory reference, pointer to a struct
 *             tee_shm
 *
 * Secure and normal world communicates pointers as physical address
 * instead of the virtual address. This is because secure and normal world
 * have completely independent memory mapping. Normal world can even have a
 * hypervisor which need to translate the guest physical address (AKA IPA
 * in ARM documentation) to a real physical address before passing the
 * structure to secure world.
 */

struct optee_msg_param_tmem
{
  uint64_t buf_ptr;
  uint64_t size;
  uint64_t shm_ref;
};

/* struct optee_msg_param_rmem - registered memory reference parameter
 * offs:       Offset into shared memory reference
 * size:       Size of the buffer
 * shm_ref:    Shared memory reference, pointer to a struct tee_shm
 */

struct optee_msg_param_rmem
{
  uint64_t offs;
  uint64_t size;
  uint64_t shm_ref;
};

/* struct optee_msg_param_fmem - ffa memory reference parameter
 * offs_lower:    Lower bits of offset into shared memory reference
 * offs_upper:    Upper bits of offset into shared memory reference
 * internal_offs: Internal offset into the first page of shared memory
 *                reference
 * size:          Size of the buffer
 * global_id:     Global identifier of Shared memory
 */

struct optee_msg_param_fmem
{
  uint32_t offs_low;
  uint16_t offs_high;
  uint16_t internal_offs;
  uint64_t size;
  uint64_t global_id;
};

/* struct optee_msg_param_value - opaque value parameter
 *
 * Value parameters are passed unchecked between normal and secure world.
 */

struct optee_msg_param_value
{
  uint64_t a;
  uint64_t b;
  uint64_t c;
};

/* struct optee_msg_param - parameter used together with struct optee_msg_arg
 * attr:       attributes
 * tmem:       parameter by temporary memory reference
 * rmem:       parameter by registered memory reference
 * fmem:       parameter by ffa registered memory reference
 * value:      parameter by opaque value
 * octets:     parameter by octet string
 *
 * attr & OPTEE_MSG_ATTR_TYPE_MASK indicates if tmem, rmem or value is used
 * in the union. OPTEE_MSG_ATTR_TYPE_VALUE_* indicates value or octets,
 * OPTEE_MSG_ATTR_TYPE_TMEM_* indicates tmem and
 * OPTEE_MSG_ATTR_TYPE_RMEM_* or the alias PTEE_MSG_ATTR_TYPE_FMEM_*
 * indicates rmem or fmem depending on the conduit.
 * OPTEE_MSG_ATTR_TYPE_NONE indicates that none of the members are used.
 */

struct optee_msg_param
{
  uint64_t attr;
  union
  {
    struct optee_msg_param_tmem tmem;
    struct optee_msg_param_rmem rmem;
    struct optee_msg_param_fmem fmem;
    struct optee_msg_param_value value;
    uint8_t octets[24];
  } u;
};

/* struct optee_msg_arg - call argument
 * cmd: Command, one of OPTEE_MSG_CMD_* or OPTEE_MSG_RPC_CMD_*
 * func: Trusted Application function, specific to the Trusted Application,
 *       used if cmd == OPTEE_MSG_CMD_INVOKE_COMMAND
 * session: In parameter for all OPTEE_MSG_CMD_* except
 *          OPTEE_MSG_CMD_OPEN_SESSION where it's an output parameter
 *          instead
 * cancel_id: Cancellation id, a unique value to identify this request
 * ret: return value
 * ret_origin: origin of the return value
 * num_params: number of parameters supplied to the OS Command
 * params: the parameters supplied to the OS Command
 *
 * All normal calls to Trusted OS uses this struct. If cmd requires further
 * information than what these fields hold it can be passed as a parameter
 * tagged as meta (setting the OPTEE_MSG_ATTR_META bit in corresponding
 * attrs field). All parameters tagged as meta have to come first.
 */

struct optee_msg_arg
{
  uint32_t cmd;
  uint32_t func;
  uint32_t session;
  uint32_t cancel_id;
  uint32_t pad;
  uint32_t ret;
  uint32_t ret_origin;
  uint32_t num_params;

  /* num_params tells the actual number of element in params */

  struct optee_msg_param params[];
};

/* OPTEE_MSG_GET_ARG_SIZE - return size of struct optee_msg_arg
 *
 * num_params: Number of parameters embedded in the struct optee_msg_arg
 *
 * Returns the size of the struct optee_msg_arg together with the number
 * of embedded parameters.
 */

#define OPTEE_MSG_GET_ARG_SIZE(num_params) \
        (sizeof(struct optee_msg_arg) + \
         sizeof(struct optee_msg_param) * (num_params))

/****************************************************************************
 * Part 2 - requests from normal world
 ****************************************************************************/

/* Return the following UID if using API specified in this file without
 * further extensions:
 * 384fb3e0-e7f8-11e3-af63-0002a5d5c51b.
 * Represented in 4 32-bit words in OPTEE_MSG_UID_0, OPTEE_MSG_UID_1,
 * OPTEE_MSG_UID_2, OPTEE_MSG_UID_3.
 */

#define OPTEE_MSG_UID_0                 0x384fb3e0
#define OPTEE_MSG_UID_1                 0xe7f811e3
#define OPTEE_MSG_UID_2                 0xaf630002
#define OPTEE_MSG_UID_3                 0xa5d5c51b
#define OPTEE_MSG_FUNCID_CALLS_UID      0xFF01

/* Returns 2.0 if using API specified in this file without further
 * extensions. Represented in 2 32-bit words in OPTEE_MSG_REVISION_MAJOR
 * and OPTEE_MSG_REVISION_MINOR
 */

#define OPTEE_MSG_REVISION_MAJOR        2
#define OPTEE_MSG_REVISION_MINOR        0
#define OPTEE_MSG_FUNCID_CALLS_REVISION 0xFF03

/* Get UUID of Trusted OS.
 *
 * Used by non-secure world to figure out which Trusted OS is installed.
 * Note that returned UUID is the UUID of the Trusted OS, not of the API.
 *
 * Returns UUID in 4 32-bit words in the same way as
 * OPTEE_MSG_FUNCID_CALLS_UID described above.
 */

#define OPTEE_MSG_OS_OPTEE_UUID_0       0x486178e0
#define OPTEE_MSG_OS_OPTEE_UUID_1       0xe7f811e3
#define OPTEE_MSG_OS_OPTEE_UUID_2       0xbc5e0002
#define OPTEE_MSG_OS_OPTEE_UUID_3       0xa5d5c51b
#define OPTEE_MSG_FUNCID_GET_OS_UUID    0x0000

/* Get revision of Trusted OS.
 *
 * Used by non-secure world to figure out which version of the Trusted OS
 * is installed. Note that the returned revision is the revision of the
 * Trusted OS, not of the API.
 *
 * Returns revision in 2 32-bit words in the same way as
 * OPTEE_MSG_CALLS_REVISION described above.
 */

#define OPTEE_MSG_FUNCID_GET_OS_REVISION 0x0001

/* Do a secure call with struct optee_msg_arg as argument
 * The OPTEE_MSG_CMD_* below defines what goes in struct optee_msg_arg::cmd
 *
 * OPTEE_MSG_CMD_OPEN_SESSION opens a session to a Trusted Application.
 * The first two parameters are tagged as meta, holding two value
 * parameters to pass the following information:
 * param[0].u.value.a-b uuid of Trusted Application
 * param[1].u.value.a-b uuid of Client
 * param[1].u.value.c Login class of client OPTEE_MSG_LOGIN_*
 *
 * OPTEE_MSG_CMD_INVOKE_COMMAND invokes a command a previously opened
 * session to a Trusted Application.  struct optee_msg_arg::func is Trusted
 * Application function, specific to the Trusted Application.
 *
 * OPTEE_MSG_CMD_CLOSE_SESSION closes a previously opened session to
 * Trusted Application.
 *
 * OPTEE_MSG_CMD_CANCEL cancels a currently invoked command.
 *
 * OPTEE_MSG_CMD_REGISTER_SHM registers a shared memory reference. The
 * information is passed as:
 * [in] param[0].attr                   OPTEE_MSG_ATTR_TYPE_TMEM_INPUT
 *                                      [| OPTEE_MSG_ATTR_NONCONTIG]
 * [in] param[0].u.tmem.buf_ptr         physical address (of first fragment)
 * [in] param[0].u.tmem.size            size (of first fragment)
 * [in] param[0].u.tmem.shm_ref         holds shared memory reference
 *
 * OPTEE_MSG_CMD_UNREGISTER_SHM unregisters a previously registered shared
 * memory reference. The information is passed as:
 * [in] param[0].attr                   OPTEE_MSG_ATTR_TYPE_RMEM_INPUT
 * [in] param[0].u.rmem.shm_ref         holds shared memory reference
 * [in] param[0].u.rmem.offs            0
 * [in] param[0].u.rmem.size            0
 *
 * OPTEE_MSG_CMD_DO_BOTTOM_HALF does the scheduled bottom half processing
 * of a driver.
 *
 * OPTEE_MSG_CMD_STOP_ASYNC_NOTIF informs secure world that from now is
 * normal world unable to process asynchronous notifications. Typically
 * used when the driver is shut down.
 */

#define OPTEE_MSG_CMD_OPEN_SESSION      0
#define OPTEE_MSG_CMD_INVOKE_COMMAND    1
#define OPTEE_MSG_CMD_CLOSE_SESSION     2
#define OPTEE_MSG_CMD_CANCEL            3
#define OPTEE_MSG_CMD_REGISTER_SHM      4
#define OPTEE_MSG_CMD_UNREGISTER_SHM    5
#define OPTEE_MSG_CMD_DO_BOTTOM_HALF    6
#define OPTEE_MSG_CMD_STOP_ASYNC_NOTIF  7
#define OPTEE_MSG_FUNCID_CALL_WITH_ARG  0x0004

#endif /* __DRIVERS_MISC_OPTEE_MSG_H */
